The present invention relates to an improved antenna, which is typically either permanently or temporarily mounted on a window, or, alternatively, on another type of partition or the like.
Antennas for window mounting are well-known in the art being typically used on the windows of vehicles for cellular car telephones, being described, for example, in the Blaese, U.S. Pat. Nos. 4,658,259; 4,779,098; and 4,804,969.
In the first two of the patents previously cited, spaced, field-cancelling conductors are attached to the window, with the antenna being placed in electrical connection therewith to provide desired field cancelling effects. However, such an arrangement is undesirable, particularly in the case where a portable antenna is provided. There, the portable antenna may be carried by the user from car to car, being hung on a car window as described in the previously cited U.S. Pat. No. 4,804,969. In that patent, coiled wire field cancelling members are provided which project laterally outwardly from the antenna housing. Thus, the structure is somewhat bulky and cumbersome, and, while operating effectively, are relatively expensive to manufacture and to assemble into the antenna unit, so that improvements are desirable.
By this invention, an antenna for mounting on glass windows is provided in which field cancelling conductive tape does not have to be attached to the window, yet the antenna may be manufactured at reduced cost and with greater ease than the antenna of the last-cited patent. Additionally, the antenna of this invention is more compact than previous designs, while exhibiting great effectiveness in signal reception and transmission.